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Patch "KVM: x86: add read_phys to x86_emulate_ops" has been added to the 4.2-stable tree

PATCH [email protected] 1 participant 1 message Dec 7, 2015

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This is a note to let you know that I've just added the patch titled

KVM: x86: add read_phys to x86_emulate_ops

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:

     kvm-x86-add-read_phys-to-x86_emulate_ops.patch

and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 7a036a6f670f63b32c5ee126425f9109271ca13f Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <[email protected]>
Date: Fri, 30 Oct 2015 16:36:24 +0100
Subject: KVM: x86: add read_phys to x86_emulate_ops
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From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <[email protected]>

commit 7a036a6f670f63b32c5ee126425f9109271ca13f upstream.

We want to read the physical memory when emulating RSM.

X86EMUL_IO_NEEDED is returned on all errors for consistency with other helpers.

---
 arch/x86/include/asm/kvm_emulate.h |   10 ++++++++++
 arch/x86/kvm/x86.c                 |   10 ++++++++++
 2 files changed, 20 insertions(+)
arch/x86/include/asm/kvm_emulate.h +10 -0
@@ -112,6 +112,16 @@ struct x86_emulate_ops {
 			struct x86_exception *fault);
 
 	/*
+	 * read_phys: Read bytes of standard (non-emulated/special) memory.
+	 *            Used for descriptor reading.
+	 *  @addr:  [IN ] Physical address from which to read.
+	 *  @val:   [OUT] Value read from memory.
+	 *  @bytes: [IN ] Number of bytes to read from memory.
+	 */
+	int (*read_phys)(struct x86_emulate_ctxt *ctxt, unsigned long addr,
+			void *val, unsigned int bytes);
+
+	/*
 	 * write_std: Write bytes of standard (non-emulated/special) memory.
 	 *            Used for descriptor writing.
 	 *  @addr:  [IN ] Linear address to which to write.
arch/x86/kvm/x86.c +10 -0
@@ -4260,6 +4260,15 @@ static int kvm_read_guest_virt_system(st
 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, 0, exception);
 }
 
+static int kvm_read_guest_phys_system(struct x86_emulate_ctxt *ctxt,
+		unsigned long addr, void *val, unsigned int bytes)
+{
+	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
+	int r = kvm_vcpu_read_guest(vcpu, addr, val, bytes);
+
+	return r < 0 ? X86EMUL_IO_NEEDED : X86EMUL_CONTINUE;
+}
+
 int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
 				       gva_t addr, void *val,
 				       unsigned int bytes,
@@ -4995,6 +5004,7 @@ static const struct x86_emulate_ops emul
 	.write_gpr           = emulator_write_gpr,
 	.read_std            = kvm_read_guest_virt_system,
 	.write_std           = kvm_write_guest_virt_system,
+	.read_phys           = kvm_read_guest_phys_system,
 	.fetch               = kvm_fetch_guest_virt,
 	.read_emulated       = emulator_read_emulated,
 	.write_emulated      = emulator_write_emulated,

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/kvm-x86-set-kvm_req_event-when-updating-irr.patch queue-4.2/kvm-x86-handle-smbase-as-physical-address-in-rsm.patch queue-4.2/kvm-x86-allow-rsm-from-64-bit-mode.patch queue-4.2/kvm-x86-add-read_phys-to-x86_emulate_ops.patch